Sewing machine

ABSTRACT

A sewing machine with a pair of wheels for conveying material layers to be joined by stitching. The conveying wheels are arranged in the stitch-forming area with each wheel associated with a member for driving said wheel continuously with the same peripheric speed. To the needle block are associated members driving said block alternately along the conveying direction. One of said wheels is retractable to allow feeding of the material layers to be joined by stitching.

United States Patent De Koninck 14 1 Feb. 12, 1974 SEWING MACHINE2,470,502 5/1949 Vesconte et a]... 112/214 2,866,426 12/1958 Wrase112/214 [76] Inventor: Alphose De Avenue, 3,216,386 11/1965 Bono 112/214x Sleeckx 84, Schaerbeek, Belgium 22 Filed; May 9 1972 7 PrimaryEXaminerWerner H. Schroeder Attorney, Agent, or FirmOtto John Munz [21]Appl. No.: 251,643

' 7] ABSTRACT Foreign Application Priority Data A sewing machine with apair of wheels for conveying June 7, 1971 Belgium 104320 material layersto be joined by stitching. The conveying wheels are arranged in thestitch-forming area with [52] US. Cl. 112/213, 1 12/214 each wheelassociated with a member for driving said [51] Int. Cl. D05b 27/10, D05b27/20 wheel continuously with the same peripheric speed, [58] Field ofSearch 112/213, 214 To the needle block are associated members drivingsaid block alternately along the conveying direction. [56] ReferencesCited One of said wheels is retractable to allow feeding of UMTED STATESPATENTS the material layers to be joined by stitching.

2,844,] 13 7/1958 Wallcnbergn, 112/213 X 4 Claims, 8 Drawing Figures o vr 11 3 O O I 20 N 1% t i. A F i. 4

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34 O 5 2 3 1' 8 J 30 2B Z- N PATENTEU FEB l 2 I974 sum 2 or 5 FIG-2.

sum 3 0F 3 PATENTED FEB] 21974 lfllllllf SEWING MACHINE This inventionpertains to a sewing machine which comprises at least one needle and twosuperposed wheels for conveying the material layers to be stitched, saidwheels engaging one another with the circumference thereof through saidmaterial layers.

A plurality of solutions have already been proposed to avoid during thesewing a wrinkling of the material layer conveyed to the needle block ofthe machine, due to said layer being driven less positively than theopposite layer brought to the hooks or the other stitchforming elementsthe drawback of a sliding between the various layers to be joined beingparticularly noticeable when finishing article edges with a ribbon ofmaterial with a low adhesion, for instance a silken ribbon.

One of the proposed solutions lies in adding to the usual mechanism withconveying claw and presser foot, a conveying roller drivenintermittently, which is arranged on the presser foot side but with astaggering relative to the claw. Such an arrangement which is not usablefor sewing narrow edgings, does not prevent the staggering of the upperlayer relative to the lower layer as the upper layer driving isdisturbed by two unaligned drives, and moreover the synchronizing of thedrive by the claw and the rollers is impossible, which also adds to animproper working of the machine.

Another proposed solution lies in arranging behind the presser foot of amachine comprising in the usual way a presser foot and a conveying claw,a pair of conveying wheels which are driven intermittently when the clawfeeds the article to be stitched. This arrangement has however thedrawback on the one hand of excluding the stitching of curved articlesand on the other hand, of causing irregularities in the work due to thejerks caused by the conveying wheel intermittent drive. In this casealso a synchronizing of both drives is impossible another drawbackresults from the spacing between the claw and the conveying wheel pairwhich is w y bo m... f r 9 Starting 9UP? WEEK- A known solution of adifferent kind, applied to machines with presser foot and conveyingclaw, lies in imparting to the needle block in addition to the usualalternating movement in and out of the material layers to be stitched,an alternating movement along the conveying direction said movements theresultant of which is an oscillating motion of the needle block about anaxis moving along the direction of the material layers to be joined,comprise an operating travel during which the needle (needles) beinglocated in the material layers, takes said layers along in the conveyingdirection together with the claw, and a dead travel required to returnthe needle block and the claw to the starting point. In this knownembodiment, half of each working cycle of the machine as far as thematerial layer feeding is concerned, is lostfor the return of the needleblock and the conveying claw consequently the operating travel of theneedle block along the conveying direction is equal to the stitchlength,in other words to the feed length of the fabric by each machine workingcycle and the tendency to driving along variable length paths of thesuperposed material layers to be joined by stitching according to .theposition thereof relative to the needle is all the more pronounced thatthe stitch length is long. Finally, as the needle block has a drivingfunction for the article to be stitched and not only a stitch-formingfunction, said block must have a strong structure whichis consequentlylittle suitable to high speeds. I

This invention has for object to obviate the drawbacks of the knownsolutions and to increase the machine operating speed. For this purposein the machine according to the invention, the wheels are arrangedsidewise relatively to the needle as considered along the stitchingdirection, the needle receives an oscillating movement along thestitching direction, between two positions lying on either side of avertical plane that passes through the wheel axes, each one of saidwheels is connected to a continuous drive member with the samecircumferential speed, and the upper wheel is provided with a raisingdevice to allow the feeding and pressing between the wheels of thematerial layers to be stitched.

It is to be understood that the combination of elements according to theinvention allows a smooth synchronized continuous feeding of thematerial layers to be joined, makes use of the complete cycle for thefeed ing of said-material layers, relieves the needle block from thestresses required for the driving and limits the operating travel of theneedle along the conveying direction, to about half the stitch lengththis set of features allows machine operating speeds Well above the meanvalue, a speed of 5,500 revolutions per minute and more may beconsidered as a practical example.

In a particularly advantageous embodiment, the conveying wheels arearranged between the machine area with the needles and the innerstitch-forming members, and a housing inside which are arranged twodriving members the one end of which projects outside the housing andbears a pinion for powering a driving pinion co-axial with the conveyingwheel, the upper conveying wheel as well as the driving pinion thereofbeing rotatably mounted on a shaft supported by a cage which isrotatably mounted about the power pinion, said shaft being connected toa lever for raising the cage by rotating thereof about the power pinion.

Other details and features of the invention will stand out from thedescription given below by way of non limitative example and withreference to the accompanying drawings, in which FIG. 1 is an elevationview partly in section and with parts broken away, of a sewing machineaccording to the invention.

FIG. 2 is an end view partly in section of the machine shown in FIG. 1.

FIG. 3 is a section view with parts broken away, along line lII--III inFIG. 2.

FIG. 4 is a section view with parts broken away, along line IVIV in FIG.1.

FIGS. 5a to 5d diagrammatically show the positions of the conveyingwheels and of a needle by different moments in the operating cycle ofthe machine according to the invention.

In the various figures, the same reference numerals pertain to similarelements.

The sewing machine according to the invention comprises a housing 1 witha lower portion 1' inside which is supported a crank-shaft 2 which isdriven by a shaft not shown and an upper portion 1" inside which issupported a main upper shaft 3 which is driven by a belt 4 from thecrank-shaft 2.

The crank-shaft 2 has a throw 5 on which swings a rod 6 hinged to anoscillating lever 7 of an axis 8 which bears in turn a pair of hooks 9which cooperate to form the stitch with on the one hand, a pair ofneedles 10 and on the other hand, a pair of spreaders 11 which areattached to an alternating-motion axis 12.

The needles 10 are attached to the end of a needle bar 13 with whichthey comprise the needle block the needle bar is slidingly' supported ina frame 14 which oscillates in a way described below. On the bar 13 isattached a small block 15 mounting the foot ofa lever 16 which is hingedon the other hand to a pivot 17 supported by a cam 18 which is made fastto the end of the main upper shaft 3. This set of members movesalternately the needles 10 along the direction of bar 13, in and out ofthe material layers of an article to be stitched, by passing through aneedle plate 19 on the housing 1.

The frame 14 is arranged at the end of a shaft 20 which is supported bybearings in the housing 1 and at the other end of which is attached thefoot of a lever 21 which is associated to an eccentric 22 mounted on themain upper shaft 3, This set of members causes the needle bar tooscillate about the axis of shaft 20.

The crank-shaft 2 bears a worm wheel 23 meshing with a worm 24 which ismade fast to a shaft 25 extending in a plane at right angle to the shaft2, slantwise from bottom to top between a level lying below the needleplate 19 and a level above said plate 19. The shaft 25 bears a pair ofspaced worms 26,27 which each mesh with a worm wheel 28,29 respectivelymounted on a shaft 30,31 in parallel relationship with the main shaft 2.Each one of said shafts 30,31 bears at that end thereof'projecting fromthe housing 1 which lies on the side of the stitch-forming members(needles 10, hooks 9, spreaders 11), a pinion 32,33 which meshes in turnwith a larger-diameter pinion 34,35 which is integral with one of thesuperposed wheels 36,37 for conveying the material layers to bestitched.

The unit comprising the lower conveying wheel 36 and the pinion 34 isrotatably mounted on a shaft 38 which is supported by a cage 39 which isconnected to the housing in 50 on that side opposite the wheel 36, thecage 39 supports through bearings 42 the shaft 30.

The unit comprising the upper conveying wheel 37 and the pinion isrotatably mounted on a shaft 40 which is fixedly mounted in a cage 41which is rotatably mounted about the shaft 31 by means of bearings 43the axis 40 projects inside a recess 44 of housing 1 where it bears thefoot of a link 45 which is hinged on the other hand on a lever 46 whichis supported by a pivot 47 projecting from the housing 1 the lever bearsan operating handle 48 which allows to retract the conveying wheel 37through rotating of the cage 41 and therewith of the unit comprised ofthe conveying wheel 37 and pinion 35 about the pinion 33 to allow thefeeding of the material layers to be stitched between the conveyingwheels 36,37.

The profile of the conveying wheel circumference is selected in anysuitable way to provide driving without slipping of the material layersto be joined by stitching. The serrated showing in the drawings is notlimitative. The construction allows moreover to exchange the wheels toadapt same to the kind of work to be performed. The lower conveyingwheel 36 passes through the needle plate so as to enter in a way knownfrom the usual conveying claws, the material layers to be stitchedfacing said wheel.

It is clear that in the machine according to the invention, the materiallayers are continuously driven on either side of the sewing plane by theconveying wheels 36,37 in the stitch-forming area, the needles 10 movingtogether with the material layers, at the same speed and along the samedirection, from that moment where they enter said layers until themoment where they leave said layers. During the return travel of theneedles to prepare for the formation of the following stitch, thematerial layers go on being fed in such a way that if as usual, theneedles remain in the material layers during half the working cycle ofthe machine, the stitch length will be substantially twice as long asthe needle path measured along the stitching line.

A working cycle of the machine according to the invention, correspondingto a 360 rotation of shafts 2 and 3, has been shown diagrammatically inFIGS. 5a to 5d.

In the 0 position, the plane of the needle bar is high and goes throughthe axis of the conveying wheels 36,37 the path of the end of needles 10has been shown in dashed lines and the material piece to be stitched hasbeen designated by refernce 51.

Between 0 and the needle bar goes down along part AB of the travelthereof, the piece 51 moving forward under the action of conveyingwheels 36,37 over one fourth of the complete cycle displacement. Between90 and the needle bar has reached the lowest travel point thereof, C,which is located on said axis while having moved forward together withpiece 51 over one fourth of the complete displacement, measured in theplane of pieceSll. Between 180 and 270, the needle bar while stillmoving along the conveying direction of the material piece 51 to bestitched over one fourth of the complete displacement, has been raisedup to level D where it comes out of said piece 51 between 270 and 360,the needle out of piece 51 goes up to point A while moving backwardsrelative to the conveying direction of piece 51, as said piece 51 goeson moving forward over the last fourth of the displacement thereof. Anew cycle then starts again.

It must be understood that the invention is in no way limited to theabove embodiements and that many changes may be brought therein withoutdeparting from the scope of the invention as defined by the appendedclaims.

1 claim 1. A sewing machine for stitching material layers, comprising:

at least one needle; and

two superimposed wheels for feeding the material layers;

an upper wheel; and

a lower wheel;

said upper and said lower wheels each mounted on a driving shaft withtheir axes of rotation in the same vertical plane horizontally parallelto each other; and

with the orbits of their circumference in pressure engagement with oneanother through the layers of said material separated by them;

means to rotate said wheels continuously at the same circumferentialspeed;

means to reciprocate said needle between two terminal positions, eachsaid position located on the opposite side of said vertical plane; and

means to raise the upper wheel to allow the feeding and pressing of saidmaterial between the said wheels, to allow the feeding and pressingbetween the wheels of the material layers to be stitched;

further comprising:

a machine area, said at east one needle located within said machinearea;

inner stitch forming members;

said wheels arranged between the said machine area and the said innerstitch forming members;

a housing;

two driving members each mounted inside the said housing with one endprojecting outside the housing;

a driving pinion coaxially mounted with each said wheel;

a power pinion for powering said driving pinion;

a cage rotatably mounted about said power pinion;

a lever means for raising the said cage;

a shaft supported by said cage and connected to said lever for raisingthe cage by rotation thereof about the said power pinion;

said upper wheel and said driving pinion rotatably mounted on said shaftabout the said power pinion.

2. A sewing machine as claimed in claim 1, which comprises a controlshaft arranged slanting upwards inside said housing, crosswise relativeto the driving shafts; said control shaft bearing two worms a pinionrotating together with one of said driving shafts;

said worms meshing with said pinions.

3. A sewing machine comprising:

a housing;

a rotary drive shaft disposed at least partially in said housing;

an upper work feeding rotary wheel;

a lower work feeding rotary wheel, which wheels form a pair of workfeeding wheels in pressure contact with one another, having their axisof rotation arranged horizontally parallel one to the other and in thesame vertical plane;

an upper and a lower rotating driving member, each for one of said workfeeding wheels, said driving members extending from a region within saidhousing to a region external thereof; connection within said housingfrom said shaft for continuously rotating said driving members;

a first pinion means mounted on the end of each driving member which isexternal of the housing;

a second pinion means mounted co-axial with each work feeding wheel,each first pinion means being in driving engagement with one secondpinion means to continuously rotate said work feeding wheels a cagerotatably mounted on that part of said upper driving member which isexternal of said housing, said upper work feeding wheel and itsassociated second pinion means being rotatably mounted on a shaftcarried by said cage; and

connecting means between said cage and an operating lever to rotate saidcage between a position wherein said upper work feeding wheel is'inpressure contact with said lower-work feeding wheel and a positionwherein said upper work feeding roller is disengaged from contact withsaid lower work feeding wheel;

stitchrforming members comprising:

a reciprocating needle carrying bar extending in a vertical planeadjacent said working feeding wheels; and

means for oscillating said needle carrying bar for shifting the needlein the direction of feed whenever it is engaged with the work betweentwo positions lying on either side of said vertical plane containingboth wheels rotating axis.

4. A sewing machine comprising:

a housing; 1

a rotary drive shaft disposed at least partially in said housing;

an upper work feeding rotary wheel;

a lower work feeding rotary wheel, which wheels form a pair of workfeeding wheels in pressure contact with one another, having their axisof rotation arranged horizontally parallel one to the other and in thesame vertical plane;

connections from said shaft for continuously rotating said lower workfeeding wheel;

a rotating driving member for said upper work feeding wheel;

said driving member extending from a region within said housing to aregion external thereof; connection within said housing from said shaftfor continuously rotating said driving member;

a first pinion means mounted on the end of said driving member;

a second pinion means mounted co-axial with said upper work feedingwheel;

said first and second pinion being in driving engagement to continuouslyrotate said upper work feeding wheel;

a cage rotatably mounted on that part of said upper driving member whichis external of said housing, said upper work feeding wheel and itsassociated second pinion means being rotatably mounted on a shaftcarried by said cage and connecting means between said cage and anoperating lever to rotate said cage between a position,

wherein said upper work feeding wheel is in pressure contact with saidlower work feeding wheel and a position, wherein said upper work feedingroller is disengaged from contact with said lower work feeding wheel;

stitch forming members comprising:

a reciprocating needle carrying bar extending in a vertical planeadjacent said work feeding wheels; and A means for oscillating saidneedle carrying bar for shifting the needle in the direction of feedwhenever it is engaged with the work between two positions lying oneither side' of said vertical plane containing both wheels rotatingaxis.

1. A sewing machine for stitching material layers, comprising: at leastone needle; and two superimposed wheels for feeding the material layers;an upper wheel; and a lower wheel; said upper and said lower wheels eachmounted on a driving shaft with their axes of rotation in the samevertical plane horizontally parallel to each other; and with the orbitsof their circumference in pressure engagement with one another throughthe layers of said material separated by them; means to rotate saidwheels continuously at the same circumferential speed; means toreciprocate said needle between two terminal positions, each saidposition located on the opposite side of said vertical plane; and meansto raise the upper wheel to allow the feeding and pressing of saidmaterial between the said wheels, to allow the feeding and pressingbetween the wheels of the material layers to be stitched; furthercomprising: a machine area, said at east one needle located within saidmachine area; inner stitch forming members; said wheels arranged betweenthe said machine area and the said inner stitch forming members; ahousing; two driving members each mounted inside the said housing withone end projecting outside the housing; a driving pinion coaxiallymounted with each said wheel; a power pinion for powering said drivingpinion; a cage rotatably mounted about said power pinion; a lever meansfor raising the said cage; a shaft supported by said cage and connectedto said lever for raising the cage by rotation thereof about the saidpower pinion; said upper wheel and said driving pinion rotatably mountedon said shaft about the said power pinion.
 2. A sewing machine asclaimed in claim 1, which comprises : a control shaft arranged slantingupwards inside said housing, crosswise relative to the driving shafts;said control shaft bearing two worms ; a pinion rotating together withone of said driving shafts; said worms meshing with said pinions.
 3. Asewing machine comprising: a housing; a rotary drive shaft disposed atleast partially in said housing; an upper work feeding rotary wheel; alower work feeding rotary wheel, which wheels form a pair of workfeeding wheels in pressure contact with one another, having their axisof roTation arranged horizontally parallel one to the other and in thesame vertical plane; an upper and a lower rotating driving member, eachfor one of said work feeding wheels, said driving members extending froma region within said housing to a region external thereof; connectionwithin said housing from said shaft for continuously rotating saiddriving members; a first pinion means mounted on the end of each drivingmember which is external of the housing; a second pinion means mountedco-axial with each work feeding wheel, each first pinion means being indriving engagement with one second pinion means to continuously rotatesaid work feeding wheels ; a cage rotatably mounted on that part of saidupper driving member which is external of said housing, said upper workfeeding wheel and its associated second pinion means being rotatablymounted on a shaft carried by said cage; and connecting means betweensaid cage and an operating lever to rotate said cage between a positionwherein said upper work feeding wheel is in pressure contact with saidlower work feeding wheel and a position wherein said upper work feedingroller is disengaged from contact with said lower work feeding wheel;stitch forming members comprising: a reciprocating needle carrying barextending in a vertical plane adjacent said working feeding wheels; andmeans for oscillating said needle carrying bar for shifting the needlein the direction of feed whenever it is engaged with the work betweentwo positions lying on either side of said vertical plane containingboth wheels rotating axis.
 4. A sewing machine comprising: a housing; arotary drive shaft disposed at least partially in said housing; an upperwork feeding rotary wheel; a lower work feeding rotary wheel, whichwheels form a pair of work feeding wheels in pressure contact with oneanother, having their axis of rotation arranged horizontally parallelone to the other and in the same vertical plane; connections from saidshaft for continuously rotating said lower work feeding wheel; arotating driving member for said upper work feeding wheel; said drivingmember extending from a region within said housing to a region externalthereof; connection within said housing from said shaft for continuouslyrotating said driving member; a first pinion means mounted on the end ofsaid driving member; a second pinion means mounted co-axial with saidupper work feeding wheel; said first and second pinion being in drivingengagement to continuously rotate said upper work feeding wheel; a cagerotatably mounted on that part of said upper driving member which isexternal of said housing, said upper work feeding wheel and itsassociated second pinion means being rotatably mounted on a shaftcarried by said cage ; and connecting means between said cage and anoperating lever to rotate said cage between a position, wherein saidupper work feeding wheel is in pressure contact with said lower workfeeding wheel and a position, wherein said upper work feeding roller isdisengaged from contact with said lower work feeding wheel; stitchforming members comprising: a reciprocating needle carrying barextending in a vertical plane adjacent said work feeding wheels; andmeans for oscillating said needle carrying bar for shifting the needlein the direction of feed whenever it is engaged with the work betweentwo positions lying on either side of said vertical plane containingboth wheels rotating axis.